Hello Dear Sven and Linus:
You are right , and When i check /sys/class/net/bat0/mesh/* and i found archlinux lost network-coding .
They were connected via a single cable as you .
Whether i need use older batman version (batman-adv and batctl 2015.2 ) ?
and our version is newest version ( Linux alarmpi 4.4.26-1-ARCH ) and hardware platform is raspberry pi B , but
i search wiki , i found kernel 4.4 will usebatman 2015.2
https://www.open-mesh.org/projects/open-mesh/wiki/Download
linux 4.4 => batman-adv 2015.2 (get batctl 2015.2 fromhere https://downloads.open-mesh.org/batman/stable/sources/batctl/).
if batman-adv don't support archlinux really , whether ubuntu will support batman-adv .
Thanks
[root@alarmpi ~]# grep '' /sys/class/net/bat0/mesh/* /sys/class/net/bat0/mesh/aggregated_ogms:enabled /sys/class/net/bat0/mesh/ap_isolation:disabled /sys/class/net/bat0/mesh/bonding:disabled /sys/class/net/bat0/mesh/bridge_loop_avoidance:enabled /sys/class/net/bat0/mesh/distributed_arp_table:enabled /sys/class/net/bat0/mesh/fragmentation:enabled /sys/class/net/bat0/mesh/gw_bandwidth:10.0/2.0 MBit /sys/class/net/bat0/mesh/gw_mode:off /sys/class/net/bat0/mesh/gw_sel_class:20 /sys/class/net/bat0/mesh/hop_penalty:30 /sys/class/net/bat0/mesh/isolation_mark:0x00000000/0x00000000 /sys/class/net/bat0/mesh/multicast_mode:enabled /sys/class/net/bat0/mesh/orig_interval:1000 /sys/class/net/bat0/mesh/routing_algo:BATMAN_IV